[link] SQL for Dummies: Demystifying The WordPress Database

Well one part of the Wordpress smoke screen sort of explained! hahaha..

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WP uses its database to store and retrieve information as and when needed. The following article gives you a crash course knowledge of the WordPress data storage.

Just in case you do not wish to get your hands dirty, you can consider trying database management plugins such as WP-DBManager or WP-Optimize. In any case, whether you ever employ SQL queries or not, it always helps to know your way around the database.